Tunnel liner



May 6, 1930.

R. V. PROCTOR ET AL TUNNEL LINER Filed Feb. 25, 1927 iNVENTOR PatentedMay 6, 1930 UNITED STATES PATENT OFFICE ROBERT V. PROGTOR AND HARRY M.SCHAAIB, OF YOUNGSTOWN, OHIO, ASSIG-NORS TO THE COMMERCIAL SHEARING &STAMPING COMPANY, OF YOUNGSTOWN, OHIO, A

CORPORATION OF OHIO TUNNEL 1.1mm.

Application filed. February 25, 1927. Serial No. 170,827.

This invention relates to tunnel liners and particularly to tunnel linerplates adapted to be assembled into a rigid metal tube-llke structure.

In ordinary practice, when tunnehng through soft earth, the hole istimbered to support the soft earth until the concrete or brick lininghas been put in place. This practice has often proved very expensive tothe contractor not only because of the actual expense of lining, butalso because of the fact that the timbering all lay outside of thetheoretical line of the concrete, and was,

therefore, extra material which had to be paid for by the contractor.This percentage of concrete has, in certain cases, run as high as 150%over and above the theoretical amount of concrete necessary for thelining.

It has heretofore been proposed to use steel plates bent to the radiusof the outside of the tunnel wall. While these plates have had certainadvantages over the old method of lining with wood, they have beendisadvantageous in that they lacked stiffness across joints be water thecorners. Moreover, trouble was frequently encountered at the corners ofadjacent plates due to the presence of a small opening which allowedwater and mud to see through. While it is not essential that the tight,it is desirable that they be so close that seepage of quicksand or otherextremely soft earth will be prevented. We provide a tunnel liner platehaving an integral flange on its several sides, the flange at thecorners presenting a unitary unjolnted structure. Stated in another way,the metal in a flange on one side of the liner extends around the cornerof the liner in an unbroken manner into the metal forming the flange ofan adjacent side. These unbroken metal corners present a substantiallysharp edge and the two flanges are at right angles" to one another.Therefore, when the plates are joined up there is no small corneropening which permits seepage.

The integral flange makes for very great stiffness of the liner. Wefurther stiffen the liner by providing ribs in the surface. As an aid toready assembling of the plates, we proto the first and last bolt videelongated bolt holes in the flanges which extend along the curved sidesof the liner.

In the accompanying drawings which illustrate the present preferredembodiment of the invention,

Figure 1 is a side elevation of a hner;

Figure 2 is an end elevation;

Figure 3 is a top plan view;

Figure 4 is a partial view of the blank from which the plate is formed;

. Figure 5 is a bottom view of a corner of the plate showing therelatively sharp corner, and

Figure 6 is a section taken on the line VIVI of Figure 5.

In the illustrated embodiment of the invention there is shown a tunnelliner comprising a body portion 2 having stiffening ribs 3 embossedtherein. The liner forms a part of the surface of a cylinder and itsbounding ed es are-defined respectively by planes perpen icular to theaxis of such cylinder and by planes containing such axis. The ribs 3extend around the circumference of the cylinder and .are hereinafterreferred to as circumferential ribs.

The body 2 of the liner is provided with flanges along each edge. Thereare end flanges 4 and circumferential flanges 5. All of the flanges areprovided with bolt holes for joining the segments together. The flanges4 have bolt holes 6 of any convenient spacing. The flanges 5 areprovided with elongated bolt holes 7 whose spacing at is substantiallytwice the distance d from the end flanges 4 holes 7. This permits ofstaggering the end joints in adjacent rows of segments. The segments areso shaped that an even number of them will make a complete circle.Another circle is built up on this first circle, but with the end form acomplete 'tunnel lining.

Figure 4 shows the blank from which the liner is stamped. The blank isbent along the chain line 8 so as to form the flanges. It will be notedthat the corner of the blank has been clipped off at substantially 45,as indicated at 9, and it has been further clipped off as indicated at10. With this form of blank oints staggered. This is continued so as toit is possible to make a substantially sharp corner which will preventseepage.

The relatively sharp corner is best shown in Figure 5. It is secured,first, by providing the blank illustrated in Figure 4, and second. byrounding off the corners of the punches so that a diagonal sectionthrough a corner is as shown in Figure 6.

Our improved plate is very stiff in all directions and is, therefore,superior to the old form of tunnel liner.

We have illustrated and described a preferred form of the invention, butit will be understood that it is not limited to this form alone, as itmay be otherwise embodied within the scope of the following claims.

We claim 1. A wrought metal tunnel liner comprising a body portionhaving integral upstanding flanges, the flanges presenting a unitaryunjointed structure at the corners of the body, the corners adjacent theedges of theflanges being relatively sharp, the flange metal at thecorners being joined to the body portion by well-rounded corners.

2. A wrought metal tunnel liner comprising a plate having integralflanges thereon, the flanges at the corners presenting a unitaryunjointed structure, the flange metal at the corners being joined withthe plate proper by well-rounded corners, the exposed edges of theflanges having sharp corners at the corners of the liner so' that theliners can be closely fitted together without leaving openings at thejoints.

3. A wrought metal tunnel liner comprising a plate having end and sideflanges, the flanges being integral with the plate and being joinedthereto along the sides and ends of the plate by a relatively sharpcorner, the flanges being integral with one another at the corners ofthe plate, the flange metal at the corners being joined to the plateproper by well-rounded corners, the exposed edges of the flanges havingsharp corners at the corners of the liner so that the liners can beclosely fitted together without leaving openings at the joints.

In testimony whereof we have hereunto set our hands.

ROBERT V. PROCTOR. HARRY M. SOHAAB.

